Proximity payment devices are in widespread use. Many are card-shaped and resemble a standard credit card in appearance although other form factors are also used. It has also been proposed to equip consumer devices, such as wristwatches and the like, with proximity payment capabilities.
A well known standard for proximity payment devices has been promulgated by MasterCard International Incorporated, the assignee hereof, and is referred to as “PayPass”. Proximity payment devices typically include a radio frequency identification (RFID) integrated circuit (IC) embedded in a plastic body or contained in a housing. An antenna is also embedded in the plastic body or housing. The antenna may allow the proximity payment device to receive a power signal from a point of sale terminal. The antenna is also used by the internal circuits to communicate information with the POS terminal, such as the payment account number, and possibly other information as well.
One issue faced by account holders with proximity payment devices is that a wrongdoer may attempt to interrogate proximity payment devices to download account numbers therefrom without their knowledge. It has been proposed to protect against this possibility by preventing proximity payment devices from transmitting the account numbers unless the user is pressing a switch on the device at the time that the device is interrogated. However, if this approach were applied to a proximity payment device provided as a wristwatch, bracelet or wristband, the user would need to engage in an awkward two-handed maneuver to have the device read by the POS terminal.